Power steering systems may use motors or other devices to assist a driver in turning the wheels of a vehicle. For any steering system, one of the primary goals is to achieve a desired level of performance for steering feel. The steering feel of a vehicle is determined by the combination of the performance of the steering system and of the vehicle's chassis.
The steering system is typically developed or tuned to accommodate the chassis. Typically, during development the chassis is changing at the same time the steering system is being developed/tuned. In some cases, if the vehicle development begins with a relatively good chassis, it is easier to tune the steering system to achieve an acceptable level of steering feel. Conversely, if the vehicle development begins with a relatively poor chassis it becomes a very difficult task to achieve acceptable steering feel through tuning of the steering system. In some cases, a desired level of performance is not achieved because issues with the chassis dominate the overall performance and exceeds the authority of tuning within the steering system.
To address these issues, modifications are made to the steering system dynamics through hardware and software design modifications. This is often an iterative process due to the number of changes to the chassis that are commonly made during development. Such iterative modifications can delay development completion time and can increase the cost of the system.